From: Greg KH <gregkh@linuxfoundation.org>
To: Stephen Hemminger <stephen@networkplumber.org>
Cc: lantianyu1986@gmail.com, alex.williamson@redhat.com,
cohuck@redhat.com, KY Srinivasan <kys@microsoft.com>,
Haiyang Zhang <haiyangz@microsoft.com>,
Stephen Hemminger <sthemmin@microsoft.com>,
sashal@kernel.org, mchehab+samsung@kernel.org,
davem@davemloft.net, robh@kernel.org,
Jonathan.Cameron@huawei.com, paulmck@linux.ibm.com,
Michael Kelley <mikelley@microsoft.com>,
Tianyu Lan <Tianyu.Lan@microsoft.com>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
linux-hyperv@vger.kernel.org, vkuznets <vkuznets@redhat.com>
Subject: Re: [PATCH] VFIO/VMBUS: Add VFIO VMBUS driver support
Date: Mon, 11 Nov 2019 18:23:22 +0100 [thread overview]
Message-ID: <20191111172322.GB1077444@kroah.com> (raw)
In-Reply-To: <20191111084712.37ba7d5a@hermes.lan>
On Mon, Nov 11, 2019 at 08:47:12AM -0800, Stephen Hemminger wrote:
> On Mon, 11 Nov 2019 01:49:20 -0800
> "Greg KH" <gregkh@linuxfoundation.org> wrote:
>
> > > + ret = sysfs_create_bin_file(&channel->kobj,
> > &ring_buffer_bin_attr);
> > > + if (ret)
> > > + dev_notice(&dev->device,
> > > + "sysfs create ring bin file failed; %d\n",
> > ret);
> > > +
> >
> > Again, don't create sysfs files on your own, the bus code should be
> > doing this for you automatically and in a way that is race-free.
> >
> > thanks,
> >
> > greg k-h
>
> The sysfs file is only created if the VFIO/UIO driveris used.
That's even worse. Again, sysfs files should be automatically created
by the driver core when the device is created. To randomly add/remove
random files after that happens means userspace is never notified of
that and that's not good.
We've been working for a while to fix up these types of races, don't
purposfully add new ones for no good reason please :)
thanks,
greg k-h
next prev parent reply other threads:[~2019-11-11 17:23 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-11 8:45 [PATCH] VFIO/VMBUS: Add VFIO VMBUS driver support lantianyu1986
2019-11-11 9:49 ` Greg KH
2019-11-11 16:47 ` Stephen Hemminger
2019-11-11 17:23 ` Greg KH [this message]
2019-11-11 17:29 ` Stephen Hemminger
2019-11-19 23:37 ` Michael Kelley
2019-11-19 23:56 ` Alex Williamson
2019-11-20 18:35 ` Stephen Hemminger
2019-11-20 19:07 ` Alex Williamson
2019-11-20 19:46 ` Stephen Hemminger
2019-11-20 20:31 ` Alex Williamson
2019-11-20 23:18 ` Stephen Hemminger
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